first you would need to close the last L5 bridge in order for them to work in a dual motherboard. what this does is make your processors into MP
next you need to see if the processors are multiplier unlocked , if they are then you can do a pin mod to allow for higher multiplier or use TMC-XP [multiplier changers]
also need to know what board you want to use , there is few to choose from,
MSI K7D Master [allows multiplier control to 12 and up to 150 fsb , and cpu voltage to 1,82]
Asus A7M266D [another dual board that works well , i been told rev 1.4 board is best and last one made?]
Gigabyte [also a board that is still being sold , check newegg refurb section as they are there now for 130 dollars] this board doesnt have cpu voltage control or multiplier control in bios , would require pin mod for cpu voltage etc
for memory i prefer ecc registered just cause i had so much trouble with two sticks that wasnt
Jen